All Rotary water pumps.

Symptoms of rotary water pump failing are excessive noise, low water pressure and the pressure gauge pointer bouncing and vibrating.

These are the general symptoms however the rotary water pump can start to seize without vibration or excessive noise but the pressure will overtime reduce.

Causes of failure are old age low mains water pressure, not using the rotary water pump for a few months will cause it to seize, and failing seals allowing water to enter the bearings.

To replace the rotary water pump, it is not normally required to remove the whole pump and motor assembly especially the clamp band fitting type however some bolt on pump heads may be difficult to access the bolts with the motor in position.

Always isolate the machine from both the mains electricity and the mains water supply before disassembling the machine.

First remove the braded pipes attached to the rotary pump head first, it’s easier while the head is held solid on the motor

Now undo the clamp ring holding the rotary pump head to the pump motor, a sharp tap may be required the separate them.

There are 2 fitting’s screwed into the rotary pump head normally one is a 90-degree bend and one is straight, make a note of which side each one fits along with the position of the 90-degree fitting, now remove the straight one first as the bent fitting will not turn 360 degrees with the straight one installed.

Refitting is the reverse however it is recommended that a small amount of thread sealer is used on the fitting threads as a precaution. Don’t forget to fit the 90-degree fitting first making sure it is pointing in the right direction. 

Once the rotary pump is installed along with all pipes tight turn on the water supply and check for leaks all should be good.

Turn on the power supply and press the star button which will run the pump and check the water pressure gauge, it should read 9 Bar, if it requires adjusting there is an adjusting screw on the side with a locking nut, release the locking nut and screw in slowly to reduce the pressure or out to increase the pressure, once you are happy that it’s 9m Bar on the gauge tighten the locking nut holding the adjusting screw in position with a screwdriver.